The present invention relates to systems and methods as used in phacoemulsification procedures, and more particularly, to irrigation or infusion sleeves that position over a phacoemulsification tip during such procedures.
Typical surgical instruments suitable for phacoemulsification procedures on cataractous lenses include an ultrasonically driven phacoemulsification hand piece with a cutting phacoemulsification (“phaco”) tip or needle and an irrigation sleeve, and a control console. The hand piece is attached to the control console by an electric cable and flexible tubing. The flexible tubing supplies irrigation fluid to the surgical site and also carries aspiration fluid from the surgical site to a waste or discard reservoir.
During a phacoemulsification procedure, the tip of the cutting phaco needle and the end of the irrigation sleeve are inserted into the anterior segment of the eye through a small incision in the eye's outer tissue. The surgeon brings the tip of the cutting phaco needle into contact with the lens of the eye, so that the vibrating tip fragments the lens. The resulting fragments are aspirated out of the eye through the interior bore of the cutting phaco needle.
Throughout the procedure, irrigating fluid is infused into the eye, passing between the infusion sleeve and the tip of the cutting phaco needle and exiting into the eye at the tip of the infusion sleeve and/or from one or more ports or openings formed into the infusion sleeve near its end. This irrigating fluid prevents the collapse of the eye during the removal of the emulsified lens, protects the eye tissue from the heat generated by the vibrating of the ultrasonic cutting phaco needle, and suspends the fragments of the emulsified lens for aspiration from the eye.
Particularly with small and/or bent phaco tips, such as 20 gauge, the irrigating fluid may exit through a distal end of the infusion sleeve. This is referred to as forward flow. Significant forward flow of irrigating fluid from the infusion sleeve may reduce the performance of the phaco tip, may impact the surgical efficiency, and may result in less than optimal clinical outcomes. Current approaches to reducing forward flow have been unsatisfactory in a number of ways. Therefore, there remains a need for an improved system for reducing or preventing forward flow during a medical procedure. The present disclosure is directed to addressing one or more of the deficiencies in the prior art.